[VOL-2570]Make skew configurable for performance metrics

Change-Id: I6db3e32147e6c11b2d268d9cfb2808b4bbe10678
diff --git a/go.mod b/go.mod
index 81af0cc..80ac494 100644
--- a/go.mod
+++ b/go.mod
@@ -10,7 +10,7 @@
 	github.com/jessevdk/go-flags v1.4.0
 	github.com/jhump/protoreflect v1.5.0
 	github.com/opencord/voltha-lib-go/v3 v3.1.13
-	github.com/opencord/voltha-protos/v3 v3.3.3
+	github.com/opencord/voltha-protos/v3 v3.4.0
 	github.com/stretchr/testify v1.4.0
 	golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45 // indirect
 	golang.org/x/time v0.0.0-20190308202827-9d24e82272b4 // indirect